Configured pop-up not working in portal map but does work in related app?!?

[erinheinrich]

Hi all,

I have configured the pop-up on the mapservice below, via Portal 10.3, but it stopped working last week - though it still shows all the configured details. When I click on a feature (eg yellow trail to the right of screenshot), I get nothing, no pop-up, no response.

I have created an app through Web Appbuilder (via Portal) and it is based on this map.

And in the app, the pop-ups work!!

I feel like i'm going slightly mad!

Any help would be appreciated.

Kind regards, Erin